Our laboratory is continuing to study mechanisms of platelet participation in thrombosis, hemostasis and coagulation. Platelets and their subcellular components are under study with particular reference to mechanisms of interaction with biochemical compounds known to specifically influence platelet behavior. Two platelet components will be studied with particular emphasis on their binding properties. these are gangliosides and proteolipids. Interactions between these lipids and compounds such as serotonin, epinephrine and adenosine diphosphate (ADP) will be studied by the technique of affinity chromatography. Gangliosides and/or proteolipids may possibly act as platelet membrane receptors for the aforementioned compounds. An understanding of platelet binding interactions such as those proposed may greatly increase our knowledge of the thrombotic process. A biochemical insight into these reactions can serve as a foundation for the synthesis of effective antithrombotic agents.